We established full three-dimensional localization of 13C MRS using polarization transfer techniques and demonstrated the successful three-dimensional localization in the human brain and significant sensitivity increases at 4T (~ factor 5 over those previously reported at 2.1 Tesla). This 13C MRS capability was then used in conjunction with 1H MRS to assign an unusually high peak to scyllo-inositol in the normal human brain by detecting an elevated intensity at 74.5 ppm.